InventoryCache = {}

function InventoryCache:new(o)
    o = o or {}
    setmetatable(o, self)
    self.__index = self
    self.data = {}
    return o
end

function InventoryCache:FindItem(item)
    local ret = -1
    for i = 1,16 do
        data = self.data[i]
        if (data ~= nil and data.name == item) then
            ret = i
        end
    end
    return ret
end

function InventoryCache:MoveItem(from, to, count)
    print("Moving items from " .. from .. " to " .. to)
    turtle.select(from)
    if(count ~= nil) then
        turtle.transferTo(to, count)
    else
        turtle.transferTo(to)
    end
    local tmp = self.data[to]
    self.data[to] = self.data[from]
    self.data[from] = tmp
end

function InventoryCache:IsSlotOpen(slot)
    return self.data[slot] == nil
end

function InventoryCache:Update()
    print("Updating cache..")
    for i = 1,16 do
        turtle.select(i)
        data = turtle.getItemDetail(i)
        self.data[i] = data
    end
end

function InventoryCache:PrintInventory()
    for i = 1,16 do
        if(self.data[i] ~= nil) then
            print(self.data[i].name .. " in slot " .. i)
        end
    end
end